The impact of stent length on stent-adjacent stenosis following transverse sinus stenting in idiopathic intracranial hypertension

OBJECTIVE: Cerebral venous sinus stenting (VSS) is an established treatment for transverse sinus (TS) stenosis associated with idiopathic intracranial hypertension (IIH). The authors' early practice favored shorter stents that only spanned the focal narrowing to reduce the metal burden. However, stent-adjacent stenosis (SAS) emerged as a significant failure mode prompting the use of longer constructs. In this study, the authors sought to compare the incidence of SAS, clinical outcomes, and angiographic findings between shorter and full-length stent constructs. METHODS: The authors conducted a retrospective analysis of patients with IIH who underwent TS stenting at Tufts Medical Center in the period from 2013 to 2023. Patients with medically refractory IIH symptoms and a significant cerebral venous pressure gradient were included. Symptom presentation, neuroimaging, venous manometry, preoperative and follow-up angiography, and clinical examination findings were recorded and analyzed across two categories of stent length: shorter (40 or 60 mm) and full length (80 mm). SAS was defined as de novo narrowing of the TS contiguous with the stent edge. RESULTS: Endovascular treatment was successful in all 60 patients included in the study (48 females, mean patient age of 39 years). Three patients were treated with 40-mm stents, 13 with 60-mm stents, and 44 with full-length 80-mm stents. SAS was documented in 8 patients (13%) and was significantly more frequent (p < 0.01) among those with shorter stents (6/16), with 3 patients requiring reintervention using a second overlapping stent. Among the 44 patients with full-length constructs, 2 demonstrated SAS at the residual unstented TS lateral to the torcular Herophili. After a mean follow-up of 40 months, 29 patients (48%) reported persistent symptoms, although there was no significant difference in this rate between the stent groups. Full-length constructs demonstrated a more favorable postoperative reduction in TS pressure gradients (p < 0.01) and lower gradients on follow-up (p < 0.05). CONCLUSIONS: SAS is a clinically relevant complication following VSS in patients with IIH and may contribute to persistent symptoms and the need for reintervention. Full-length stent constructs extending from the sigmoid sinus to the torcula significantly reduce the incidence of SAS and are associated with better hemodynamic outcomes following VSS.